System for feeding wood waste to furnaces



Fe 1930. l w. E. ALU NGTQN 1,746,456

SYSTEM FOR FEEDING WOOD WASTE TO FURNACES Filed Aug. 28, 1926 3 Shets-Sheet 1 Feb.'1l, 1930. w. E. ALLINGTON 1,746,456

SYSTEM FOR FEEDING WOOD WASTE TO FURNACES Filed Aug. 28, 1926 3 Shets-Sheet 2 YE EL 14 2 22am, E. AIR/07ml;

Feb. 11, 1930. w, g, ALUN TON 1,746,456

SYSTEM FOR FEEDING WOOD WASTE TO FURNACES Filed Aug. 28, 1926 5 Sheets-Sheet 5 Iqyg g Patented F4. 11, 1930' PATENT OFFICE WILLIAM E. ALLINGTON, OF CHICAGO, ILLINOIS SYSTEM FOR FEEDING WOOD WASTE TO FURNACES Y Application filed- August 28, 1926. Serial No. 132,079.

The invention relates to improvements in systems for feeding wood waste to furnaces. One of the objects is to feed wood waste, a byproduct of wood working factories to furnaces to be therein burned in an economical manner to generate steam in suitableboilers associated therewith.

A further object is to provide means to feed said waste to the furnaces in suitable quantim ties intermittently or at variable and controlled speed as may be required from time to time to produce the most efiicient combustion.

Another object is toprovide'an improved reservoir within which an excess supply of material above that required may be deposited and means to feed the material therefrom" to the furnaces independently of the rate at which the material is fed into the reservoir.

Another object is to provide a new and effective manner of moving the waste thru conduits and from the reservoir in which a surplus supply of material is maintained to be drawn from as may be required to produce the most eflicient combustion of the material in the furnace. i

A further object is to provide a new arrangement of conduits by which admeasured 80 quantities of material may be reliably fed into the furnace.

Other objects, advantages, benefits and refinements will become apparent to persons skilled in the art from a consideration of the following description and drawings in which Figure 1 is a vertical section of a typical plant in which my system is embodied.

Figure 2 is an enlarged elevational view taken on line II-II of Figure 1.

Figure 3 is an enlargedsectional view taken substantially on line IIIIII of Figure 2.

Figure 4 is a section taken substantially on line IV-IV.of Figure 3.

Figure 5 is a section similar to Figure 4. Figure 6 is a vertical section thru part of the direct feeding mechanism.

As shownon the drawings: 7 In Figure 1 the system is shown rather schematically in which 10 is a reservoir, 11.

material is received having fallen from the reservoir into the hopper by gravity, and 12 is aboot, which is substantially a part of; the hopper and 12' is a supplementary boot from which material is fed directly into the furnace 13. 14 is a steam boiler in which steam is generated by the fire in the furnace.

15 is a steam engine by which the conveying machinery in the boots and hopper are driven. 16 is a train of gearing between the 50 conveyors and engine and 17 is the cylinder of a pressure-responsive device for controlling the speed of the engine and thereby the quantity of fuel fed into the furnace by variation of steam pressure in the boiler.

The reservoir 10 is tapered in shape with the larger end down and its axis in a vertical plane. At the upper-end .of the casing a feeder pipe 18 feeds chips, sawdust, bark,

small slabs and the like into the reservoir or casing 10. The reservoir being much larger at 1ts bottom end, such material will not jam I or become wedged therein. The hopper 11 having its larger upper end immediately be low t e larger lower end of the reservoir 10 receives the material therefrom by the action of gravity.

In Figures 2 and 5 the single hopper terminates in two boots 12 to feed two furnaces from a single reservoir or to provide two streams of fuel for the same furnace.

Between the pair of boots 12 there is an intermediate tapered ridge 19 in the hopper 11.

The hopper 11 each side of the ridge 19 which terminates at 21 (Figure 3) to provide an opening 22 into the boot 12 thru a down spout 23.

On each side of the hopper there are shown three conveyors 24, 25 and 26. The two first mentioned conveyors 24 and 25 arranged near the inclined wall 27 of the hopper and parallel therewith on shafts 24' and 25' respectively.

The conveyor 26 is located near'the ridge 19,

on a shaft 26'. Y

The object of these conveyors is to loosen up the material in the hopper and to move it to the opening 22 and into the spout 23 from whence it will fall down into the boot 12.-

has a bottom wall 20 on 85 The conveyors 24, 25 and 26' are of n ovel construction. For example, the first group of like convolutions are 9 inches in diameter and 9 inch pitch. The second group, on the same shaft, of which there may be three convolutions, are 10 inch diameter and 10 inch pitch and the third group may be 11 inches in diameter and 11 inches pitch. These various diameters and pitch inclinations conform to standard sizes and answer the purposes herein disclosed admirably.

The material is moved laterally thru the hopper from the right hand to the left hand, Figure 3. The movement of the heterogeneous material mass is accelerated during its progress by. change of pitch between the adjacent groups of convolutions and the material so moved is not packed because the volumetric capacity of the conveyor is increased during transit coextensive with its increase in speed.

Another novel feature of these conveyors is the direction of their rotation as indicated by the arrows in Figure 4. In each. instance the top surface is caused to turn away from the adJacent outer side wall of the hopper 11. The spiral is arranged to permit this direction' of rotation andmovethe material away from the outer side Walls of the hopper 11 toward the ridge 19. If this were not done, the material would arch as its volume was being contracted or condensed and it would no longer pass fromthe hopper into the boot below.

The conveyor 24 rotates slower than the conveyors 25 and 26. The object is the better to loosen up the material so that it will not be moved along in condensed compacted mass and thereby caused to wedge.

The increased speed of movement, caused by greater degree of pitch and the corres nding increase in volumetric capacity of .t e

conveyor convolutions moves the mass in a more attenuate stream without loss ofcapacity of operation. a

In the supplementary boot 12 a conveyor 7 29 on shaft 29' moves the material laterally that comes down the-main boat12- into the supplementary boot 12. V

The conveyor 29 on shaft 29' moves the material into the furnace 13 there to consumed.

The conveyor 29 is rotated at a relatively high velocity. This is done for the purpose of better distribution of thematerial as it is fed into the furnace. In the event that very fine material, such as sawdust should sift down from the hopper 11- and enter the supplementary I boot 12, the conveyor 29 will prevent its undesirable accumulation due to the relatively high speed of said conveyor 29. The supplementary boot 12 and conveyor 29 therein in close proximity with the furnace fire serves as a fire seal and prevents the fire from reaching back to the mass of combustibles in the reservoir 10.

The arrangement of conveyors and gearing on the left side, as shown in Figure 2, are duplicates of the arrangement on the right side.

A jack shaft 32 is driven by a steam engine 15. A sprocket wheel 33 on shaft 32 drives chains 34 which drives sprockets 3131 on the shafts 29. A sprocket gear 35 drives shaft 37 by chain36. A spur gear wheel 38 on shaft 37 meshes with a similar spur gear wheel 39 and rotates shaft 40 in an opposite direction which is correct for driving the conveyors on left side.

, The chains for driving the shafts 24'25 and-26 are clearly shown in Figure 2.

The pressure responsive device for controlling the speed of the engine 15 to vary feed of fuel into the furnace consists of the cylinder 17 having a vertically movable piston 43 therein. The cylinder 17 is connected to the boiler by steam pipe 44. A pipe 45 connects the cylinder of the engine with the boiler. A shut off valve 46 in pipe 45 controls the flow of steam from the boiler to the engine. A stem 47 passes thru a head 48 in cylinder 17 and is pivotally connected to an arm 49 extending from the valve. A spring 50 normally holds the arm 49 in position in which the valve is fully open. Increase of steam pressure raises piston 43 against the yielding resistance of spring 50 and decreases the flow of steam thru pipe 45 to engine 15. Thus the variation of steam pressure in the furnace varies the amount of fuel fed to the boiler.

A very important feature of the invention lies in the provision of an expansion chamber 52 located at the delivery end of conveyor 26 and over the down spout 23. The expansion chamber 52 is. located beyond the front wall of the reservoir 10 thereby relieving any material. delivered thereto from any vertical pressure from the material in said reservoir 10.

This chamber 52 is separated from the upper part of the front end of the hopper 11 by an apron 53. The apron 53 is hinged at 54 and freely. swingson said hinges. The lower edge of the apron carries a weight-bar 55 which normally maintains the apron in a vertical plane when there is no unbalanced pressure on its two sides.

One of the objects of the apron is to prevent finely comminuted material, such as sawdust and the like from sifting through from the reservoir 10 into the expansion chamber 52 and then into spout 23 and into the boot 12 and supplementary boot 12.. I 7 By the use of the apron, materialthat will be fed to the lower conveyor '29 is determined solely by the speed and capacity of the conveyor 26 and those thereabove.

The contents of the chamber 52 is also re- "lieved of all pressure due solely to the weight of material in the reservoir and hopper, and rovides space for material fed laterally y conveyor 26, to. expand about the time it is ready to drop thru the down spout 23.

The apron 53 also serves as a fire barrier, to some extent.

The capacity and speed of conveyor 29 is limiting the patent granted hereon, otherwise than necessitated by the prior art.

I claim as my invention:

1. A system for conveying conglomerate. material and feeding it to a furnace including atapered storage reservoir; means to feed said material into the smaller upper end thereof; a conveyor below the larger end of the reservoir arranged to loosen the ma,- terial and feed it laterally with respect to the axis of said reservoir, and a relatively high speed conveyor to feed said materials directly into the furnace.

2. A system for conveying conglomerate material and feeding it to a furnace including a storage reservoir of tapered shape arranged with its axis in a vertical plane and with the larger end below to discharge into 'a hopper; means to feed material into the reservoir and connected to its upper smaller end; a hopper below the reservoir to receive material from said reservoir; a conveyor arranged to feed said material laterally and rotated in a direction, to prevent packing thereof, and a relatively high speed conveyor arranged to feed said material directly into a furnace.

3. In a system of the character described, a material storage reservoir comprising. a

tapered casing arranged withits apex uppermost and with its axis in a vertical plane; means at the apex to feed materials into said casing; a hopper structure located below said casing arranged with its smaller end upper-.

most and with its axis in' a vertical plane; means for feeding materials into said casing at its upper end; a tapered hopper below said casing, tapered in an opposite direction, with its larger end uppermost; moving means in the hopper to maintain materials therein in a loosened state and to move the materials laterally thereof; a boot below the hopper to receive materials from the hopper and a conveyor in therboot to move the materials at a faster rate from the hopper.

5. In a system of the character described, a materials reservoir comprising a tapered casin to receive wood waste from a woodworking establishment, said casing located with its axis in a vertical plane and its larger end at the bottom; an opening at the smaller top end into which to feed said materials; a hopper tapered with its larger end below said casing to receive material falling from said casing; materials loosening means to prevent materials from packing ,insaid hopper and arranged to move the materials laterally thereof into a boot, and a conveyor in the boot to accelerate the movementof said materials in thesame direction 6. A storage reservoir for conglomerate masses of wood waste comprising a casing tapering axially from its lower larger end to a smaller upper end and having an opening at its upper end into which to feed materials, in combination with a hopper at the larger lower end in which to receive materials falling by gravity from said casing into the hopper, and means to feed said materials" through and laterally from saidhopper.

7. A system for conveying conglomerate waste and feeding it to a furnace including a storage reservoir having a taperedpart with a large base and tapered upwardly, to contain a supply of said materiah'meansto feed material into said reservoir connected I to its smaller upper end; means to loosen the material while in the reservoir and to convey it and discharge it laterally of the reservoir and a'relatively high speed conveyort'o feed the material therefrom into a furnace.

8. A system for conveying. conglomerate 'waste and feeding it to a furnace, including a storage reservoifhaving a tapered part furnace.

9. A system for conveying wood waste materials from woodworking machinery as fast as made, to a storage reservoir, including means connecting said reservoir and the source of supply; moving means to loosen the materials while in the reservoir andto discharge said materials laterally of the reservoir; a speed controlled relatively high speed conveyor to feed materials therefrom into the furnace and meansacting as a fire seal between the furnace and the reservoir.

10. A system for conveying wood waste materials from wood working machinery to a furnace, including a reservoir; a conveyor for conveying the materials therefrom, and a closed expansion chamber at the delivery end of said conveyor out of the exit path of said .materials.

11. A system for conveying wood waste materials from wood working-machinery to a furnace, including a reservoir; a conveyor for conveying the materials therefrom; a. closed expansion chamber at the delivery end of said conveyor out of the exit path of said materials, and a swinging apron above the conveyor separating said chamber from said reservoir.

' 12. A" system for conveying wood waste materials from wood working machinery to a furnace, including a reservoir; a conveyor for conveying the materials from the reservoir; another conveyor for conveying said materials delivered to it by the first conveyor, and an expansion chamber at the delivery end of the first conveyor.

13. A system for conveying wood waste materials from wood working machinery to a furnace, including a reservoir to receive said materials as made; ahorizontal screw conveyor for conveying said materials laterally therefrom; a down spout to receive said materials, and an expansion chamber above said spout and separated from said reservoir.

14. In a material conveyor system the combinationwith a hopper, of conveyor means therein, an expansion chamber connecting with the end of said hopper, and a movable apron separating said expansion chamber from the hopper.

15. A material transfer device comprising a supply reservoir, a hopper connected therewith, a boot extension at one end of said hopper, an expansion chamber located between said hopper and said boot extension, conveyor mechanisms in said hopper adapted to be rotated at different rates of speed, and conveyor means in said boot extension adapted to be rotated at a higher speed than the conveyors in said hopper.

' 16. In a material transfer device, the comfeed hopper, of a plurality of screw conveyorsv of different lengths mounted therein, with each of saidwconveyors constructed of a plurality of groups of spiral convolutions having different pitches and diameters, and means for driving said conveyors at different rates of speed.

19. In a material feed device of the class described, the combination with a hopper having a ridge formed longitudinally therein, of a plurality of spiral conveyors mounted in said hopper on each side of said ridge, and means for driving the conveyors on each side ofthe ridge at different rates of speed.

20. In a material feed device of the class described, the combination with a hopper, of means for supplying material thereto, a down spout formed at one end of the hopper, conveyors in said hopper for delivering material to the down spout, an expansion chamber at one end of said hopper above said down spout, a boot extension connected with the hopper below said down spout, and a conveyor in said boot extension for receiving material from the down spout and advancing the same through said boot extension.

In testimony whereof I have hereunto subscribed my name.

IL-LIAM E ALLINGTON.

bination with a hopper having a ridge formed longitudinally therein, of a plurality of conveyors on opposite sides of said ridge, and means for rotating said conveyors in a direction downwardly towards said ridge to obviate packing of material between the conveyors and the side walls of the hopper.

17. In a material feed device of the class described, the combination with a hopper, of a plurality of screw conveyors mounted therein rotatable at different rates of 

